A wide variety of goods are handled, such as during manufacturing or processing, by automated means. Such goods may include any number of different configurations having various sizes and shapes. For example, bags of different sizes, shapes, compositions, and external marking characteristics are used in various industries to encapsulate loose product so that the product can be efficiently consolidated, transported, distributed, and marketed. These bags are often manufactured and processed by automated means, such as to cut flattened tubes of appropriate lengths, seal an end or ends to form a bag or close a filled bag using stitching or adhesive, print information and other markings on a surface thereof, stack and pallet of the finished, unfilled bags, filling the bags with product, etc. Accordingly, handling of goods, such as the aforementioned bags, may include operations such as justifying edges of goods in a stack, clamping or compressing goods in a stack, moving one or more goods between processing stations, orienting one or more goods, etc. using robotic manipulators.
A basket tine clamp robotic manipulator is sometimes used in the automated manufacturing and processing of goods. FIGS. 1A and 1B illustrate, in highly simplified fashion, the operation of a typical prior art basket tine clamp. Basket tine clamp 100 shown in FIGS. 1A and 1B may be disposed on the end of a robotic arm member (not shown) to provide an interface with goods, while the robotic arm member is controlled to move basket tine clamp 100 and any goods disposed within basket area 101. Accordingly, basket tine clamp 100 includes angled tines 111 and 112 for engaging and incarcerating goods for robotic handling operations, such as moving goods between processing stations. Although only 2 angled tines are shown in FIGS. 1A and 1B, it should be appreciated that a plurality of angled tines may be included on both the left and right sides of basket tine clamp 100 (e.g., a series of angled tines disposed behind angled tines 111 and 112 along an axis extending into the paper) to form a three-dimensional basket area.
Angled tines 111 and 112 of FIGS. 1A and 1B are disposed on pivot members 121 and 122 respectively. Pivot members 121 and 122 are coupled to support member 131, providing pivot points about which pivot members 121 and 122 rotate. Additionally, pivot members 121 and 122 are coupled to a respective one of linear actuators 141 and 142, providing movement forces to pivot members 121 and 122. Linear actuators are coupled to brace 132, which itself is coupled to support member 131.
In operation, linear actuators 141 and 142 are operated to extend and retract. Because the proximal ends of linear actuators 141 and 142 are coupled to brace 132, providing rigid support of the actuators with respect to support member 131, distal ends of linear actuators 141 and 142 impart translational forces on upper ends of pivot members 121 and 122. With pivot members 121 and 122 coupled to support member 131 through respective pivot points, lower ends of pivot members 121 and 122, and correspondingly angled tines 111 and 112, are provided rotational movement in accordance with the actuator induced movement of the upper ends of pivot members 121 and 122. As shown in FIG. 1B, when linear actuators 141 and 142 are retracted, angled tines 111 and 112 are disposed such that basket tine clamp 100 is in an open position (e.g., no goods are engaged and/or incarcerated by basket tine clamp 100). However, when linear actuators 141 and 142 are extended, angled tines 111 and 112 are disposed such that basket tine clamp 100 is in a closed position forming basket area 101 (e.g., goods may be engaged and/or incarcerated by basket tine clamp 100, such as for moving the goods between processing stations).
The configuration illustrated in FIGS. 1A and 1B implement separate linear actuators to manipulate the tines of opposing sides of the basket tine clamp. Such a configuration is problematic in that if the movement of the actuators, and thus the movement of the tines, is not synchronized the goods may be mishandled. For example, angled tines 111 operating out of synchronization of angled tines 112 may cause goods disposed in basket area 101 to move left or right, thereby resulting in misplacement of the goods by the robotic actuator. Such inaccurate placement of goods can result in damage to the goods, unorganized or unstable stacking of goods, etc. Accordingly, in the configuration illustrated in FIGS. 1A and 1B, linear actuators 141 and 142 would need to be closely matched (e.g., provide substantially the same extension/retraction rate and stroke) as well as being controlled to operate in synchronization.
It can be readily appreciated from the configurations illustrated in FIGS. 1A and 1B that various sizes and shapes of goods are not easily accommodated by basket tine clamp 100. For example, basket area 101 defined by angled tines 111 and 112 has a fixed width dimension (W) defined at least in part by the location of the pivot points on support member 131. However, many goods have a side width that does not correspond to the foregoing basket area width dimension. If such goods were attempted to be manipulated by basket tine clamp 100, such handling would likely result in the failure to adequately incarcerate the goods during movement or processing, damage to the goods by basket tine clamp 100, etc.
Although the foregoing width dimension might appear to be alterable through controlled rotational movement of pivot members 121 and 122, in practice that is not the case. In particular, if pivot members 121 and 122 are under/over rotated in an attempt to alter the working width of basket area 101, angled tines 111 and 112 will no longer be in the proper geometry to engage and/or incarcerate goods. That is, the lower portion of angled tines 111 and 112 will no longer be oriented parallel to support member 131 when engaging or incarcerating goods. Such a situation can lead to failure to adequately incarcerate the goods during movement or processing, damage to the goods by basket tine clamp 100, etc.
Moreover, adjustment of the relative positions of the pivot points used by pivot members 121 and 122 to alter the foregoing width dimension is problematic. For example, even ignoring the difficulties associated with relocating each pivot member's pivot point on support member 131, additional alterations of basket tine clamp 100 would likely be required, such as to make corresponding adjustments with respect to linear actuators 141 and 142. Accordingly, it is not uncommon for different robotic manipulators to be required for handling different goods.
Although not shown in FIGS. 1A and 1B, basket tine clamp 100 may include additional tines (not shown), such as straight tines used for justifying edges of a stack of goods prior to angled tines 111 and 112 engaging the goods. These additional tines would, similar to the angled tines discussed above, require adjustment to accommodate an altered basket area width, thus further restricting the ability of basket tine clamp 100 to accommodate goods of different sizes and shapes.
It is often desirable for manufacturing or other processing operations to be performed at relatively high speeds in order to reduce handling times and costs. However, the long stroke of linear actuators 141 and 142 typically require appreciable time to complete a cycle, and thus may not be suitable for use at higher speeds. Alternatively, linear actuators 141 and 142 may be driven rapidly to their extremes (e.g., fully extended and retracted without dampening the stroke) in order to facilitate higher speed operation. However, the present inventors have discovered that such operation results in premature failure of the actuators, and thus is less than an ideal solution for providing high speed operation.
Basket tine clamp 100 illustrated in FIGS. 1A and 1B is a highly simplified representation of prior art basket tine clamps. However, the basket tine clamps heretofore available generally have one or more of the foregoing disadvantages associated therewith. Accordingly, the discussion above is believed to be applicable to a wide variety of prior art basket tine clamps.